Increase MSRV to 1.67 (#3234)

* Bump MSRV to 1.67

* clippy fixes

* cargo clippy: inline format args

* Add `clippy::uninlined_format_args` to cranky lints

* Fix clippy on wasm

* More clippy fixes

crates/egui_extras/src/datepicker/popup.rs

@@ -428,6 +428,6 @@ fn month_name(i: u32) -> &'static str {
         10 => "October",
         11 => "November",
         12 => "December",
-        _ => panic!("Unknown month: {}", i),
+        _ => panic!("Unknown month: {i}"),
     }
 }